namespace System.Threading.Tasks
{
	internal class TaskContinuation : IContinuation
	{
		private readonly Task task;

		private readonly TaskContinuationOptions continuationOptions;

		public TaskContinuation(Task task, TaskContinuationOptions continuationOptions)
		{
			this.task = task;
			this.continuationOptions = continuationOptions;
		}

		private bool ContinuationStatusCheck(TaskContinuationOptions kind)
		{
			if (kind == TaskContinuationOptions.None)
			{
				return true;
			}
			int kindCode = (int)kind;
			TaskStatus status = task.ContinuationAncestor.Status;
			if (kindCode >= 65536)
			{
				kind &= ~(TaskContinuationOptions.PreferFairness | TaskContinuationOptions.LongRunning | TaskContinuationOptions.AttachedToParent | TaskContinuationOptions.ExecuteSynchronously);
				switch (status)
				{
				case TaskStatus.Canceled:
					switch (kind)
					{
					case TaskContinuationOptions.NotOnCanceled:
						return false;
					case TaskContinuationOptions.OnlyOnFaulted:
						return false;
					case TaskContinuationOptions.OnlyOnRanToCompletion:
						return false;
					}
					break;
				case TaskStatus.Faulted:
					switch (kind)
					{
					case TaskContinuationOptions.NotOnFaulted:
						return false;
					case TaskContinuationOptions.OnlyOnCanceled:
						return false;
					case TaskContinuationOptions.OnlyOnRanToCompletion:
						return false;
					}
					break;
				case TaskStatus.RanToCompletion:
					switch (kind)
					{
					case TaskContinuationOptions.NotOnRanToCompletion:
						return false;
					case TaskContinuationOptions.OnlyOnFaulted:
						return false;
					case TaskContinuationOptions.OnlyOnCanceled:
						return false;
					}
					break;
				}
			}
			return true;
		}

		public void Execute()
		{
			if (!ContinuationStatusCheck(continuationOptions))
			{
				task.CancelReal();
				task.Dispose();
			}
			else if ((continuationOptions & TaskContinuationOptions.ExecuteSynchronously) != 0)
			{
				task.RunSynchronously(task.scheduler);
			}
			else
			{
				task.Schedule();
			}
		}
	}
}